Add-Migration initial -v Build started Build failed or Update-Database Failed
Solution:
- Make sure the solution is building right, clean and rebuild, if any project fails, fix it.
- Use dot net tool through command prompt to add the migration it will give you clear information
dotnet ef migrations add MigrationName -v
Now fix the issue, in my case I needed to add reference to Microsoft.EntityFrameworkCore.Design
So I installed Microsoft.EntityFrameworkCore.Tools and it fixed the issue.

if still looking for answers check this post
Happy Coding!